As best I can tell, cruise lines primarily use Ensenada as a port of embarkation for ships that are going to Hawaii and as a port of debarkation for ships coming back to North America from Hawaii because a U. S. law called the "Jones Act" forbids any ship of foreign flag from permanently debarking passengers in the United States who embarked at a different U. S. port unless the ship has, in the interim, called at a "distant" foreign port. The "Panama Canal" cruises between Florida and California have ports of call en route on Aruba, Curacao, or the South American contenent -- all of which are "distant" under U. S. law -- and thus are legal.